2.3　Splicing and Correction

2.3.1　The splicing of the material should adopt equal strength welding manner;when the attachment weld joint strength is less than the base metal strength,the reinforcement shall be done.

2.3.2　When field welding H-shaped steels,the spacing of the splicing weld joint of the flange plate and the splicing weld joint of the web plate shall not be less than 200mm.The splicing length of the flange plate shall not be less than 2 times of the plate width and shall not be less than 500mm.The splicing width of the web plate shall not be less than 300mm,the length shall not be less than 600mm,and the splicing weld joint spacing of the web plate should not be less than 200mm.

2.3.3　The measures to reduce welding deformation shall be taken when splicing materials,the plainness,offset and buckling shall meet the requirements of"The Code of Welding for Power Plant"(DL/T 869).

2.3.4　When heating carbon structural steels and low-alloy structural steels for correction,the heating temperature shall not exceed 900℃.The low-alloy structural steel shall be carried out with natural cooling after heating and correction.

2.3.5　The minimum curvature radius and maximum bending vector height for cold correcting and cold bending of steels shall be in accordance with those specified in Table 2.3.5.

Table 2.3.5　Minimum curvature fadius and maximum bending vector height for cold correcting and cold bending(mm)

Note:r refers to curvature radius;f refers to bending vector height;L refers to bending chord length;t refers to steel plate thickness;b refers to the leg width of the angle steel,channel steel and I-shaped steel;h refers to the height of the channel steel and I-shaped steel.

2.3.6　The allowable deviation of the steel that after correction shall be in accordance with those specified in Table 2.3.6.

Table 2.3.6　Allowable deviation of steel after correction(mm)

Note:Δ—allowable deviation of steel after correction.